![Septimal major second on B7b](https://upload.wikimedia.org/wikipedia/commons/f/f7/Septimal_major_second_on_B7b.png)
In music, the septimal whole tone, septimal major second, or supermajor second is the
musical interval exactly or approximately equal to an 8/7 ratio of frequencies.
[Andrew Horner, Lydia Ayres (2002). ''Cooking with Csound: Woodwind and Brass Recipes'', p.131. . "Super-Major Second".] It is about 231
cents wide in
just intonation
In music, just intonation or pure intonation is the tuning of musical intervals
Interval may refer to:
Mathematics and physics
* Interval (mathematics), a range of numbers
** Partially ordered set#Intervals, its generalization from numbers to ...
.
[Leta E. Miller, Fredric Lieberman (2006). ''Lou Harrison'', p.72. .] 24 equal temperament does not match this interval particularly well, its nearest representation being at 250 cents, approximately 19 cents sharp. The
septimal whole tone may be derived from the
harmonic series as the interval between the
seventh
Seventh is the ordinal form of the number seven.
Seventh may refer to:
* Seventh Amendment to the United States Constitution
* A fraction (mathematics), , equal to one of seven equal parts
Film and television
*"The Seventh", a second-season e ...
and eighth harmonics and the term ''septimal'' refers to the fact that it utilizes the
seventh harmonic
The harmonic seventh interval, also known as the septimal minor seventh, or subminor seventh, is one with an exact 7:4 ratio (about 969 cents). This is somewhat narrower than and is, "particularly sweet", "sweeter in quality" than an "ordinar ...
.
It can also be thought of as the octave inversion of the 7/4 interval, the
harmonic seventh
The harmonic seventh interval, also known as the septimal minor seventh, or subminor seventh, is one with an exact 7:4 ratio (about 969 cents). This is somewhat narrower than and is, "particularly sweet", "sweeter in quality" than an "ordinar ...
.
![Origin of seconds and thirds in harmonic series](https://upload.wikimedia.org/wikipedia/commons/7/7b/Origin_of_seconds_and_thirds_in_harmonic_series.png)
No close approximation to this interval exists in the standard
12 equal temperament
Twelve-tone equal temperament (12-TET) is the musical system that divides the octave into 12 parts, all of which are equally tempered (equally spaced) on a logarithmic scale, with a ratio equal to the 12th root of 2 ( ≈ 1.05946). That result ...
used in most modern western music. The very simple
5 equal temperament is the smallest system to match this interval well. 26 equal temperament matches this interval almost perfectly with an error of only 0.4 cents, but at the cost of the significant flatness of its major thirds and fifths.
31 equal temperament
In music, 31 equal temperament, 31-ET, which can also be abbreviated 31-TET (31 tone ET) or 31- EDO (equal division of the octave), also known as tricesimoprimal, is the tempered scale derived by dividing the octave into 31 equal-sized steps (equ ...
, which has much more accurate fifths and major thirds, approximates 8/7 with a slightly higher error of 1.1 cents.
References
{{Intervals
Seconds (music)
7-limit tuning and intervals
0008:0007